'''Henry Dircks''' FRSE
FCS (26 August 1806 – 17 September 1873) was an English engineer who is considered to have been the main designer of the projection technique known as ''Pepper's ghost
'' in 1858. It is named after John Henry Pepper
who implemented a working version of the device in 1862. Dircks also investigated attempts at the invention of a perpetual motion
device, writing that those who sought to create such a thing were "half-learned" or "totally ignorant".